petraeus. general john allen is the top u.s. commander in afghanistan. officials are investigating him for, quote, inappropriate communication with jill kel kelley. she's the woman that got the petraeus investigation started. the pentagon is looking at more than 20,000 pages of documents and e-mails between kelley and general allen. 20,000. officials tell the ap that some of the material was, quote, flirtatious. general allen denies having an affair with kelley, who we know was also friends with general petraeus. joining me now is michael isikoff, national investigative correspondent for nbc news. he's been breaking some of the big details on this case over the last few days. michael, first, thanks for being here tonight. >> thank you. good to be with you. >> now, let me ask, general allen is now under investigation for his relationship with jill kelley. what can you tell us about the relationship and what can you tell us about miss kelley. >> we should say we don't know for sure. as you pointe